Process of recovering nickel from silicious ores.



react with the ADOLPHE, CHALAS, OF PHILADELPHIA, PENNSYLVANIA.

PROCESS OF RECOVERING- NICKEL FROM SILICIOUS ORES.

Specification of Letters Patent.

Patented May 12, 1908.

Application filed September 6, 1907. Serial No. 891,676.

To all whom it may concern:

Be it known that ILADOLPHE CHALAs, a citizen of French Republic, residing at Philadelphia, in'the count-y of Philadelphia and 5 State of Pennsylvania, have invented certainnew and useful Improvements in Processes of Recovering Nickel from Silicious Ores, of which the following is a specification.

This invention is a process of recovering nickel from nickel-iron silicate ores, free from co per, such as are foundin New Caledonia.

n the first stage of the process, the ore is reduced with the 1production of an alloy' of nickel and iron. he reduction is preferably effected at a high tem erature in an electric furnace, to insure goo separation of the alloy from the highly-silicious and magnesian sla The iron is eliminated from the alloy, .as ar as possible, by oxidation and scorification, for example by bessemerizing the alloy in an acid converter. The resulting ferronickel is then cast into convenient shape for use as anodes.

In the second stage of the process, the ferro-nickel anodes are placed in an electrolytic cell having nickel-sheet cathodes and containing as an electrolyte an aqueous solution of a nickel-ammonium-salt, preferably the sulfate. As electrolysis proceeds, pure nickel is deposited on the cathode, while nickel and iron are dissolved from the anode as double ammonium sulfate. During electrolysis, the solution is continuously circu lated from the cell through a filter containing a body of. precipitated nickelic hydroxid, which reacts upon the dissolved ferrous salt with production of nickel sulfate and precipitation of ferric hydroxid. The solution, thus freed from iron and containing an additional. amount of nickel e uivalent to the removed iron, is continuous y returned to the cell. The nickelic hydroxid used for the preci itation of iron is electrol tically produced from anodes of ferro-nickeli' such as result from the first stage of the processf For this purpose, the ferro-nickel anodes are placed in an auxiliary electrolytic cell having sheet cathodes of nickel or iron and containing as an electrolyte an aqueous solution of an alkalimetal salt, for example sodium chlorid. As electrolysis proceeds, nickel and iron are dissolved from the anodes as chlorids, while a sodium hydroxid solution is produced at the cathode. These two solutions, when mixed, roduction of nickelous and ferrous hydroxi s, Which precipitate, and sodium chlorid, which dissolves and regenerates the electrolyte. Itis preferable to prevent the mixing of the anodic and cathodic solutions within the cell, by providing it with a diaphragm and mixing them as they flow out of their separate compartments. The

brine, carrying the precipitates in suspen- .sion, is circulated through a filter-press,

which retains the hydroxids, the clear solution returning to the cell.

When the filter-press has been filled with the precipitated hydroxids, their peroxida-' tion is effected by circulating through the mass an aqueous solution of an alkali-metal hlypochlorite, produced, for example, by the e ectrolysis of a cold dilute solution of sodium chlorid. .The nickelous and ferrous hydroxids are thus readily peroxidized and the hypochlorite is reconverted into sodium chlorid, which is relectrolyzed. After complete eroxidation, the body of hydroxids in the ter is Washed by circulating water through it and is then ready for use in the secon stage of the process. The nickelic hydroxid, alone, enters into reaction, the small amount of ferric hydroxid mixed with it remaining inert. When the nickel hydroxid in the filter has been completely dissolved and replaced by preci itated ferric hydroxid, the stream of clectro yte is diverted to a second filter, filled with nickelic hydroxid, and the first filter is emptied, cleaned and refilled. Commercially, four filters, or sets of filters, are preferably employed, which are worked in rotation. As one filter 'is being filled with nickelic hydroxid, the contents of a second previously-filled filter are undergoing peroxidation; a third filter containing the dperoxidized precipitatingagent is being use in the second stage of the process and a fourth exhausted filter is being emptied and cleaned.

, The process of recovering nickel from the ferro-nlckel anodes is cyclic, the reagents being continuously regenerated. The nickel precipitated in the second stage of the process is in its purest commercial form. The ferric hydroxid remaining in the filter is a byproduct of some value, and may be calcined to colcothar of the finest quality.

I claim:

1. The process of recovering nickel from nickel-iron ores, which consists in smelting the ore and producing ferro-nickel, casting the alloy into anodes, electrolytically dissolving the anodes, continuously precipitating the dissolved iron by circulating theelectrolyte in contact with a body of aprecipitating agent; and redepositing the dissolved nickel.

2. The process of recovering nickel from nickel-iron ores, which consists in smelting the ore and producing ferro-nickel, casting the alloy into anodes, electrolytically dissolving the anodes, continuousl precipitating the dissolved iron by nicke ic h droxid, and redepositing the dissolved nicke 3. The process of recovering nickel from nickel-iron ores, which consists in smelting the ore and producing ferro-nickel, casting the alloy into anodes, electrolytically dissolving the anodes, continuously precipitating the dissolved iron by circulatin the electrolyte through a body of nickelic? droxid, and redepositlng the dissolved-nicks 4. The process of recovering nickel from nickel-iron ores, which consists in smelting the ore and producing ferro-nickel, casting the alloy into anodes, electrolytically dissolving the anodes, ing the dissolved iron by circulating the electrolyte through a body of nickelic hydroxid, redepositing the dissolved nickel, electrolytically dissolving other anodesof ferro-nickel in an aqueous solution of an alkali-metal salt, mixing the anodic and cathodic products and preci itating nickelous hydroxid, peroxidizing t e precl itate, and employing the nickelic hydroxi to precipitate dissolved iron in the second stage of the process.

5. The cyclic process of recovering nickel from ferro-nickel, which consists in electrolytically dissolving anodes of ferro-nickel, redecontinuously precipitatpositing the nickel, preci itating the dissolved iron by continuous y circulating the electrolyte through. a vessel containing a body of nickelic h droxid until the reagent has been exhauste then diverting trolyte to a second vessel containin a body of nickelic hydroxid, em tying the st vessel, filling it with a body of nickelous hy= droxid, peroxidizing said nickelous hydroxid, and subsequently re-passing the electrolyte through the first re-charged vessel.

6. Thecyclic process of recovering nickel from ferro-nickel, which consists in electrolytically dissolving anodes of ferro-nickel, redepositing the nickel, preci itatin the dissolved lIOII by continuous y circu ating the electrol te through a vessel containing a body ol' n-ickelic hydroxid until the reagent has been exhausted, then diverting the electrolyte to a secondvessel containin a body of nickelic hydroxid, em tying the stvessel, filling it witha body of nickelous hydroxid, peroxidizing said nickelous hydroxid, subsequently re-passing the electrolyte through the first re-charged vessel, successively divertin 'the electrolyte to third and fourth charge vessels, andsuccessively recharging and re-diverting the electrolyte to the second, third and fourth vessels, in sequence with the first.

the elec- In testimony whereof, I afiix mysignature in presence of two witnesses.

v ADOLPHE OHALAS. Witnesses:

E. J. LAvINo, J. W. HALE. 

